Oct 16, 2008

Sound quality is relative

We all know that, right? Right. Who am I kidding? Most people don't notice the difference between 96kbps 4x re-encoded mp3 and FLAC. Of course it depends on your setup. Headphones, mp3 players. All of it makes your experience better (or worse).

Since I bought my first Koss Porta Pro headphones I realized that there are headphones and HEADPHONES. With some you don't even hear the important parts, while others make you realize how much noise there is in the source :). And so my music collection is now mostly flac, high quality ogg or vbr mp3. Normally I don't care about the size of music files. Storage is not that expensive these days. But I have an old Cowon U3 music player (still cannot find anything better) with only 2GB of memory. Of course that's where size comes into play. What I usually do is convert music to lower bitrates (160 kbps vbr usually) before transfering them to the player. But I don't keep those converted versions around since I don't have that much space lying around :). So I am wasting time chosing files to transfer, then converting them and finally copy them to player.

Manually converting and then transferring files is kind of a bummer though. Now I realized...I can actually program right?! So how about making a FUSE virtual filesystem on top of vfat filesystem on the player. This virtual filesystem would convert music files being copied to the filesystem to specified format in background. Processor speeds are fast enough to do this more-less realtime these days so why not?

How will this affect my workflow? Compare:

NowVirtual FS
  • Copy files to temporary directory
  • Convert big files to lower bitrates
  • Copy files to mp3 player
  • Copy files to mp3 player
So far this is just an idea. I don't know of any other project doing the same thing (there are a few dealing with general data compression but not media files specific).

Expect more to come (just don't expect deadlines :) ).

*EDIT* As it happend there are already FUSE project that do exactly what I had in mind. I guess I should check the page more often. The projects are GSTFS and MP3FS where the first one seems more promising and flexible.

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Oct 11, 2008

We need CAPTHHA

I am pretty sure everyone has seen CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) before. Maybe you didn't know the (full) name but you have encountered it when registering accounts, posting comments or accessing some parts of web. You know, those annoying things that are exercising your ability to recognize distorted words with weird backgrounds.

CAPTCHAs are used to protect against automated attacks. For example automatic registration of new users on Gmail would create great opportunities for spammers. CAPTCHAs are mostly working, even when they get "hacked" from time to time. The biggest problem? They are reaching levels where even humans are having problems reading the letters. I still have nightmares when I remember CAPTCHAs used on RapidShare. Telling cats from dogs was not that easy for me somehow. I am not sure about "hackability" of reCAPTCHA, but as far as usability goes, it's one of the best ones for me. Too bad only a few sites are using it.

The main problem of CAPTCHAs is not the complexity but relay attacks and human solvers from 3rd world countries paid for solving thousands of CAPTCHAs a day. What we really need is CAPTHHA (Completely Automated Public Test to tell Humans and Humans Apart). Computer science is far from being able to tell humans with "clean" intentions from those being paid to get past the defences. One solution would be to issue certificates of "humanity" signed by central authority. You could then ban users that were misusing their certificates. There are of course privacy and security problems with this approach, not to mention financial "issues", so I guess this is not how it's gonna work.  Other approaches have also been tried, but they usually have problems with disabled people. I am certainly interested how Computer Science solves this problem.

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Oct 3, 2008

GFuture

I'm slowly starting to feel like Google Fanboy(tm), but Big G has made an interesting announcement recently. Dubbed "Clean Energy 2030", proposal tries to encourage several ways to achieve usage of "clean" energy by year 2030. I suggest you read it, especially if you like sci-fi. Basically they suggest 3 complementary things to do:
  1. Reduce demand by doing more with less - in other words energy efficiency.
  2. Develop renewable energy that is cheaper than coal (RE<c) - concentrate on solar, wind and geothermal energy.
  3. Electrify transportation and re-invent our electric grid.
Of these, first two seem OK. But electrifying transportation? Especially in US where you cannot buy car with engine less than 2000cc? I will watch closely. I still remember those sci-fi movies that showed flying cars in year 2000 and I am still dissapointed there are almost none.

I would love to see future come sooner, possibly while I'm still alive, but I am a little bit sceptical. Google might chip-in with generous 45$ mil this year, but will goverments follow? I doubt it. Still, hope dies last. I still have this dream of Earthlings being one big nation where it doesn't really matter which part of Earth are you from. It just matters you are not from Qo'noS or Minbar. And this "cheap energy for everyone" initiative reminds me of these dreams. Oh well, one can dream.

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